1. Technical Field
The present invention relates to a stapler of a flat type in which ends of a wire staple are driven flat after they have penetrated and fastened together sheets of paper.
2. Background Art
A stapler, which is stationery for fastening sheets of paper, is an inevitable item as one of office materials, and there have been made many proposals on staplers. In the staplers, there are two types: one is a type in which distal end portions of a staple are bent curvedly after they have penetrated and fastened sheets of paper and the other is a type in which end portions of a staple are bent flat after they have penetrated and fastened sheets of paper.
A general flat type stapler includes a base portion having a clincher, a magazine which houses staples, a handle which is rotatably attached to a portion of the base portion which lies in the vicinity of an end thereof, a driving blade disposed at a distal end portion of the handle and adapted to drive out a wire staple in the magazine towards the clincher in association with rotation of the handle, and furthermore, a table having a clincher surrounding portion and adapted to cause the clincher surrounding portion to ascend or descend relative to the clincher, a slider made to slide in such a manner as to permit a descending action of the clincher surrounding portion at a predetermined timing in association with a clinching action of the table, and a slider pushing member fixed to the handle to cause the slider to slide through rotation of the handle.
In the stapler configured as has been described above, since when it is grabbed in such a manner as to shorten the distance between the handle and the base portion, the slider pushing member causes the slider to slide, a locking state between the table and the slider is released, whereby the table is allowed to descend, and a staple is pressed between the driving blade and the clincher in such a manner that distal ends of the staple are bent to fasten sheets of paper.
Staplers which are each made up of two members which can rotate a clincher are proposed in the Japanese Examined Utility Model Publication No. 63-43027 and the Japanese Examined Utility Model Publication No. 2-48229. In these staplers, when the distance between a handle and a base portion is shortened, the clincher rotates in such a manner that an upper portion of the clincher is made into a flat surface, so as to bend flat distal ends of a staple.
In addition, in such staplers, there are a hand-held type stapler which is used by being grabbed by the hand and a desktop type stapler. A basic construction of this desktop type stapler is substantially the same as that of the hand-held type stapler. However, the desktop type stapler is larger in size than the hand-held type stapler, and since when in use, the handle member is lowered by the weight of the user being applied thereto, a large number of sheets of paper can be fastened.
In the flat type stapler, when the slider is caused to slide to lower the clincher surrounding portion, since the clincher surrounding portion descends drastically, there is caused a problem that an impact is produced at the time of clinching, and this makes it difficult to effect clinching.
In addition, in the desktop type stapler, large force is necessary to fasten a large number of sheets of paper, and where the handle portion is made large to make use of the principle of the lever to reduce the force required for clinching for fastening such a large number of sheets of paper, the balance of the stapler is deteriorated due to the handle portion being too large, and this causes a problem that in the event that a strong force is applied to the handle portion, a rear end of the stapler is caused to float. Furthermore, where the base portion is made large to improve the balance of the stapler, there is also caused a problem that the stapler becomes large in size.